1. Field of the Invention
This disclosure relates generally to video information processing, and more specifically, to a video de-interlacer which converts interlaced video information into progressive video information based on motion residue compensation.
2. Description of the Related Art
The interlaced video format is widely used primarily because of the technology development of the video industry. The current generations of television (TV) standards, for example, are primarily based on the interlaced video format. The progressive video format, however, is preferred for the newer display technologies, such as liquid crystal display (LCD), plasma, digital light processing (DLP), etc. For progressive scan video information, the video is displayed line by line from top to bottom rather than by field. For interlaced scan, every other horizontal line of the video is displayed in separate fields and each frame is completed in two passes. In particular, each frame or picture is divided into two fields including an odd field and an even field, in which the odd and even fields are displayed one at a time in alternating fashion. Because interlaced video is composed of two fields that are captured at different moments in time, interlaced video frames exhibit motion artifacts when both fields are combined and displayed at the same moment and the video contains motion.
A de-interlacer is used to convert interlaced video into non-interlaced or progressive video for display. Many solutions exist for performing the de-interlacing function. The relatively unsophisticated solutions simply copy odd lines to even or vice-versa or display the odd and even fields together. If the de-interlacing function is not done properly, however, the displayed video contains a significant amount of visual artifacts especially when the video contains a significant amount of motion. More sophisticated solutions are available, but such solutions generally consume a significant level of processing power and bandwidth (including bus and memory bandwidth), and are relatively costly. It is desired to convert interlaced video into progressive scan video while ensuring a relatively high level of visual quality. It is further desired to perform the de-interlacing function with improved performance in low cost or portable devices. It is desired to provide a low cost or portable system which requires a minimal amount of bus and memory bandwidth while providing a reasonably high quality signal appropriate for smaller displays typically in portable or automobile configurations.